Info: These gifs were created by simulating Gray Scott's model of reaction diffusion on a 2D grid. Reaction diffusion systems are widely studied and researched because their are argued to be linked to the chemical / biological processes that are responsible for pattern formation in nature (zebra stripes, leopard spots, etc). In addition, reaction diffusion systems exhibit beautiful motion when simulated and visualized. The gifs above showcase different growth patterns and oscillations in RD systems.

In simple terms, reaction diffusion systems model how one or more substances (i.e. gases or liquids) change and/or combine when mixed in a container. The reaction part of the model describes what happens chemically when the substances combine together (i.e. maybe an entirely different substance is created and introduced into the mix). The diffusion part of the model defines how the substances propagate (i.e. diffuse) in the container (2D or 3D space they are mixed in). If you're interested in learning more, check out Reza's instructable on: 3D Printed Reaction Diffusion Patterns.